Identify the compounds A, X and Z in the following reactions :
(i) A + 2HCL + 5H2O → 2NaCI + X
X → HBO2 → Z
A is Borax which reacts with HCl in the presence of water to give Orthoboric acid(X).
Upon heating Orthoboric acid Gives metaboric and further on heating gives the compound Z i.e. Boron trioxide.